Casing perforator



R. R. CHUM CASING PERFORATOR Filed Feb. 14. 1923 2 Sheets-Sheet 1 Jiuv22. 1924.

R. R. CRUM CASING PERFORATOR Filed Feb. 14 1923 2 Sheets-Sheet 2 1....,...w..w a@

, MMM/ Patented july 22, i924.

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CASING PERFORATOE Application tiled February 11.1., 1923. Serial No.618,919.

ToalZ/wham. z't'may concern:

Beit known that i, RoLAND R. CHUM, a citizen of the United States,residing at Whittier, in the county of Los Angeles and State ofCalifornia, have invented a new and useful Casing Perforator, of whichthe following is a specification.

This invention relates to aperforating device such as used in oil wellractice to perforate a casing.4 In the dri ling ofvan oil well it isoften necessary to perforate an inner casing and an outer casmg, As thewalls of these casings are frequently separated by a considerable spacethis operation is diiiicult to perform. The (general object of thisinventlon is to provi e' a practical and simple tool for this urposewhich will operate effectively to per orate both casin s, and which isconstructed to withstand t e heavy thrusts and strains to which it issubjected in lforcing the perforating tool through the walls of bothcasings; also to provide improved means for facilitating the positioningand anchoring of the perforating device at the point desired, and toprovide a construction which will insure easy control and operation ofthe tool and the anchoring mechanism.

Further objects of the invention will appear hereinafter.

The invention consists in the novel parts and combination of parts to bedescribed hereinafter. all of which contribute to produce an 'efficientcasing perforator.

A preferred embodiment of the invention is described in the followingspecification whilev the broad scope of the invention is pointed out inthe appended claims.

In the drawing:

Figure 1 is a side elevation of a perforator embodying my invention,

Fig. 2 is a longitudinal section through the perforator upon an enlargedscale, the upper portion of the perforator being broken away. This viewshows the parts in the relative position which they have when the deviceis being lowered into position in the casing,

Fig. 3 is a view similar to Figure 2 but representing the parts in therelation which thev have when the device is about to be anchored`preparatory to receiving the blow which will drive a perforator toolthrough the casing,

Fig. 4 is a view similar to Figure 3 showing the device after the blowhas been struck and the erforator tool has been driven through t ecasing walls,

Figs. 5 to 9 inclusive are horizontal sections upon an enlar ed scale,taken at the points indicated by t e section lines on Fig.

4, and

Fig. 10 is a diagrammatic view illustrating the operation of the toolWhere the outer casing has been cemented in.'

My invention concerns the body of the device which carries theperforator tool and also concerns the holding device which cooperateswith the body to facilitate the actuating of the tool to cause it toperforate the casing. The construction is such that in the operation ofthe device in lowerin the body to position in the casing, the bo y ofthe device o erates to shove down in the casing a hol ing device whichengages the casing and is capable of supportingl itself within thecasing. This holding device is connected to the body by means which willpermit an upward shifting movement of the body when it reaches theposition in the casing where the perforation is to take place. Adownward shifting movement of the body then, through the agency of theholding device,` effects the anchoring of the body to the casing, afterwhich a jarring lforce or blow actuates the tool to perforate the casinTn the preferred construction the body l of the device comprises anupper member 1 and a lower member l". The lower end of the body may beprovided with a nose 4 which may be screwed in position and secured by apin 5 (see Fig. 2). The body l is provided with gripping means, forexample, two slips 6 6 which may be mounted on inclined guides 7 atdiametrically opposite points on the lower portion of the member 1b.This gripping device or slips 6--6 is connected by suitable means with aholding device 8 located below the bod The holding device is preferablycarrie on a stem 9 which is connected at its upper end to the slips 6 bymeans of a key 10 running in slots 11 in the lower end of the lowermember. Any suitable construction may be adopted at this point whichwill operate to anchor the body to the casing 12 after the body has beenlowered to position in the well where the perforation is to be made.

'lower collar 15. Both of these collars are loose on the stem 9. Inorder to support the holding device and normally maintain its upper endagainst the nose 4 I provide a coil spring 16 on the stem, the lower endof which rests upon a collar 17 fixed on the stem. If desired, thiscollar 17 may be in a position such that the lower collar 15 restsagainst it'w-hen the upper collar 14 is held against the nose 4. Thisspring 16 also operates to pull the stem 9 downwardly and prevents thegripping device from operating while the body is being lowered toposition. y In operating the device, when the body 1 is given an upwardshifting movement the stem 9 will slide upwardly through the collars 14,15. In this connection it should be'understood that the holding member 8operates to support itself in the casing by frictional Contact of thebars 13 with the casing wall. I provide means for latching the holdingdevice at a relatively lower position on the stem whenv the stem hasbeen shifted upwardly with the body 1 as suggested. For this purpose Iprovide a spring latch 18 which may be placed in a slot in the side ofthe stem (see Fig. 2).` This catch is forced outwardly by a small spring19 and has a shoulder 20 on its outer edge. By pulling the stem upwardlythe catch will snap over the collar 15 and this will latch or lock theholding device in a lower position on the stem and leave a space betweenthe nose 4 and the upper end of the holding device. By reason of thisspace it is then possible to shift the body 1 downwardly by a movementwhich is independent of the holding device. `I utilize this movement toactuate the gripping device to anchor the body 1 to the casing. In thepresent instance the slips 6 being loose on the ends of the key 10 aresimply forced outwardly by the inclined guides 7 and the teeth 21 on theslips bite into the wall of the casing and securely anchor the lowermember 1b to it. After the body has been anchored in this way theperforator tool 2 is then actuated to perforate the casing. In thepresent instance I prefer to accomplish this by constructing the body 1of two members l and 1b as descrbed'and connect these two members insuch a way as to permit a limited longitudinal movement of the memberswith respect'to ea'ch other. This may be accomplished simply by means ofa key 22 which may be carried by the upper member l, and which runs in alongitudinal slot 23 in the member 1b. The members 1El and 1b are soconstructed that a relative longitudinal movement of one with respect tothe other will operate the perforator tool. In the present instance thismay be accomplished in a very simple manner by provid'- ing a cam faceor cam 24 just below the end of the tool 2 which normally han s in aninclined position (see Fig. 2). V'hen a jarring force occurs the uppermember la moves downwardly and the lower edge of vent such al movementwhile the entire device is being lowered to position in the well. Forthis purpose I may provide a frangible or destructible member 25 of softwood or similar material which I place between two shoulders 26 and 27formed respectively on the members 1ft and 1b. This piece of wood is, ofcourse, frangible and simply breaks or fails under the force of thejarring blow, and thereby permits the relative downward movement of theupper member 1 which actuates the tool.

It is obvious that other means may be used for actuating the tool andIdo not limit myself to the actuation of this tool merely through therelative movement of two body members.

In constructing the device the spring 16 should be sufficiently strongto support the holding device against the nose 4 and this holds the stem9 in its extended position with the slips 6, 6 normally retracted, butthe friction developed by the casing on the holding device should besufficient to enable the spring to be compressed b theupward movement ofthe collar 17 wit out developing sufficient force in the spring to causethe holding device to travel upwardly and follow the upward movement ofthe nose 4.

I shall now describe the general mode of operation of the device. Figure2 shows the relation of parts in lowering the device to position in thecasing. When the device arrives at the position where the perforation isto be made the body 1 is yshifted upwardly. In this movement thelholding device 8 supports itself in he casing and permits the stem 9 toslide upwardly through the loose collars 14 and 15. As this upwardmovement occurs the spring 16 becomes compressed by the collar 17 butdoes not shift the holding device upwardly; as the stem slides upwardlyt/he catch 18 comes above the collar 15 and the shoulder 20 snaps overthe upper face of the collar, and this operates t0 hold the stem in arelatively elevated position on the holding device 8; or in other wordsthe holding device is locked in a relamoasve tively lower position onthe stem. This leaves a gap between the nose 4 and the upper end of theholding device which will permit a downward shifting movement of the bodThis downward shifting movement e ects the application of the grippingdevice and anchors the lower member 1b to the casing. After this thedown jar disrupts the separator member or block 25, thereby permittingla relativelongitudinal movement of the upper member la with respect tothe lower member 1b. As this relative downward movement occurs the tool2 strikes the camface 24 and is driven through the casing walls (seeFig. LL). Y

By providing an extra long tool in place of the tool 2 the same may bemade to perforate not only'ai inner casing but an outer casing as well,(see Figs. 5 and 10)'. ln Fig. 5 the mode' of operation of the device isillustrated when the casings are not cemented in. Under thesecircumstances when the perforating tool 2 operates, the

inner casing 12 backs up against the wallv of .the outer casing l2a andthis takes the thrust of the tool in the perforating movement. Fig. l0illustrates the operation of the tool where an outer casing 12bl hasbeen cemented in. ln this case the body of the' device simply backs upagainst the wall of the inner casing l2 and the cement holds the innercasing in position and resists the thrust of the tool when it is ,forcedthrough the two walls of the casings.

lt is obvious that by maintaining the device at a certain level it canbe slightly rorated between each perforating operation and in this wayperforations can be placed in a circumferential arrangement around thecasing wall. Also, if desired, the device may be pulled up to a higherlevel and a similar row of perforations placed above a lower row.

lt is understood that the embodiment of the invention described hereinis only one of the many embodiments this invention may ytake and I donot wish to be limited in the practice of my invention nor in my claimsto the .particular embodiment set forth.

What I claim is:

l. ln a casing perforator, the combination of a body, a perforator toolcarried thereby, said body comprising two relatively movable members, aholding device carried by the body and operating to support itselfwithin the casing, anchoring ,means for one of said relatively movablemembers controlled through the agency off the holding device, saidrelatively movableirnembers constructed so as to cooperate 4when given adown jar to actuate the anchoring means to grip the casing, and meansoperating by theI relative movement of said-body members to each otherto. actuate the perforator tool.

2. ln a casing perforator,`the combination of a bod a perforator toolcarried thereby, said bo y comprising two relatively movahle'members,separator means for temporarily preventing relative movement between thebody members, a holding device operating to supportitself within thecasing, means for anchoring one of said body members to the casingcontrolled through the agency of the holding device, said-separatormeansv operating under the application of a down jarring force, topermit relative movement of the body members on each other, said bodymembers having means cooperating t0 actuate the perforator tool by adown jarring movement of one of said body members.

3. In a casing erforator, the combination of a body, a perfldrator toolcarried thereby, said body comprising two members constructed to slidelongitudinally relative to each other, separator means cooperating withthe body members to prevent relative longitudinal movement of the bodymembers with respect to each other, a holding device below said bodyoperating to support itself within the casing, means vfor anchoring oneof said body members to the casing 'controlled through the agency of theholding device when supporting itself within the casing, said separatormeans operating `under the application of a jarring force to permitrelative movement of the body members on each other, said body membershaving means cooperating during the said relative movement to actuatethe tool.

4. In a casing perforator, the combination of a body, a perforator toolcarried thereby, said body comprising a lower body member and an upperbody member constructed to slide longitudinally on each other','afrangible member cooperating with the body members to prevent relativelongitudinal movem'ent of the body members with respect to each other, aholding device below the body operating to support itselt` within thecasing, means for anchoring one of said body members to the casingcontrolled'through the agency of the holding device, said frangiblemember operating to break under the application of a down jarring forceand thereby permit downward movement of the upper body member,- one ofsaid body members having means cooperating to actuate the perforatortool by the said downward movement of the upper body member produced bythe jarring force.

5. n a casing erforator, the combination of a body, a perftdrator toolcarried thereby, said body comprising a pair of members guided to slidelongitudinally with respect to each other, a holding device below thebody operating to support itself within the casing, anchoring-means foranchoring one of said body members to the casing controlled through theagency of the holding device, a rangible member for temporarilypreventin longitudinal sliding movement of the body members relative toeach other until a time after the operation of the anchoring means, saidbody members having means cooperating to actuate the tool by theapplication of a force sufficient to disrupt the frangible member.

6. In a casing perforator, the combination of a body consisting of anupper body member and a lower body member mounted to slidevlongitudinally with respect to each other, a holding device supportedfrom the body and having means for engaging the casing and operating tosupport itself within the casing, means for anchoring the lower bodymember to the casing controlled through the agencyof the holding device,separator means for temporarily preventing relative longitudinalmovement between the body members and operating after the lower bodymember has been anchored, and under the application of a jarring forceto permit the relative movement of the body members, said body membershaving means cooperat ing to support ythe tool and actuate the same bythe said relativemovement of the body members.

' 7 In ay casing perforator, the combination of a body consisting of anupper member and a lower member connected together to permit a limitedlongitudinal sliding movement of the members with respect to each other,a perforatortool supported on one ot the body members, means on theother body member for actuating the tool when a relative movement of thebody members occurs, to drive the tool through the casing, means foranchoring one of the body members to the casing, and a frangible memberbetween the body members operating to fail under a jarring blow andpermit the relative movement which actuates the perforator tool.1

8. In a casing perforator, the combination of a body consisting of anupper body member and a lower body member, said members being'connectedto permit a limited relative longitudinal sliding movement with respectto each other, slips movably mounted in the lower body member, a holdingdevice connected with the slips operating to support the slips withinthe casing, said lower Vbody member having guideways diverg'ing in anupward directlon arid cooperating with the slips when supported by theholding device, to force the same against the casing and anchor thelower body member to the casing, a frangible member for temporarilypreventing longitudinal movement of the body members with respect toeach other, a perforator tool movably mounted on the upper body member,and means on the lower body member operating when the jarring forceoccurs to engage the tool and drive the same through the casing, saidfrangible member operating to disrupt and permit the relative movementof the body members which actuates the perforator tool.

9. In a casing perforator, the combination of a body, a perforator toolcarried thereby, said body comprising an upper body member and a lowerbody member movable longitudinally with respect to each `casing wall andresting at its upper. jend against the lower end of the lower bodymember to enable. the same to shove the holding member down the casingwhen the perforator is being lowered to position in the casing, acollar, on the stem for .engaging the spring, latching means cooperatingin an upward movement of the body and the stem, to compress the springand latch the holding device in a lower position on the stem, andthereby permit a downward shifting movement of the body independently ofthe holding device, the said lower body member having means operatingduring said downward shifting movement of the lower body member foractuating the gripping means to anchor the lower body member to thecasing, and a frangible member between the upper body member and thelower body member preventing a relative movement of the body members inlowering the body to position in the casing, and operating under theapplication of a jarring force to fail and permit a relative slidingmovement off the upper body member on the lower body member, said bodymembers having means cooperating to actuate the tool by the saidrelalend loose on said stem and a' collar at its lower end loose on saidstem, and having friction bars connecting said collars and for engagingthe casing, a collar fixed on the stem to engage the ower collar of thecage, a spring around the stem thrusting against the stems fixed collarand thrusting at its upper end against the upper collar of the ca hoding device and hold the gripping means against engagement with thecasing, the lower end of said body engaging the upper collar of the ca ein lowering the perforator to position. wit the casing, said frictioage, said spring operating to support the j vthe cae in the upwardshifting movement of the dy to compre the spring and support the holdingdevice in 'alower position on the stem, thereby permitting a downwardshifting movement of theA body independent y of the holding device, saidbody having means cooperating with the gripping means to anchor the bodyto the casing by a downward movement ofthe body thereafter, and aperforator tool carried bythe body and actuated by a jarring forceapplied to the body.

11. In a casing perforator, the combination of a body, a'perforator toolcarried thereby, a stem extending downwardly from the body, a holdingdevice mounted on the stem at a relatively elevated point on the stemand engaged at its upper vend by the lower end of the bodyduring the.movement of lowering the body to position in the casing, grippingmeans, means for holdinflv the same on the stem tol prevent longitudinalmovement of the gripping means along the stem, but permitting itsoutward movement from the stem,'said holding means operating to supportitself in the casing when the body is given an upward shifting movement,means cooperating with the holding means after the said upward shiftingmovement to latch the holding means on'the stem at a relatively lowerposition thereby permitting a downward shifting movement of the bodyindependently of the holding device, sald body having means cooperatingwith the gripping means in said downward shifting movement to move thegripping means outwardly against the casing, and anchor the body to thecasing, and means for actuating the perforator tool by a downward jarrinforce after the said anchoring has taken p ace.

12. Ina casing perforator, the combination of a body, a perforator toolcarried thereby, a stem extending downwardly from the body, a holdingdevice mounted on the stem at a relatively elevated point on the stemand engaged at its upper end by the lower end of the body during themovement of lowering the body to position in the casing, gripping means,a key for holding the same on the stem to revent longitudinal movementof the gripping means along the stem, but permitting its outwardmovement from the stem, said holding device operating to support itselfin the casing when the body is given an upward shifting movement, meanscooperating with the holding device after the said upward shiftingmovement to latch the holding device on the stem at a relatively lowerposition thereby permitting a downward shifting movement of the bodyindependently of they y,holding device, said body having meanscooperating with the ,gripping means in said downward shifting movementto force the ipping means outwardly against the casing, and anchor thebody to the casing, means for actuating the perforator tool by adownward jarring force after the said anchoring has taken place, andmeans associated with the stem for supporting the holding device tomaintain the same 'against the lower end of the 'body when lowering theperforator to' position in the casing.

13. In a casing perforator, the combination of a body, a perforator toolcarried thereby, said body comprising a lower body member and an upperbody member guided to slide longitudinally on the lower body member,said lower body member having inclined guide-ways diverging from eachother in an upward direction, gripping means mounted to slide in theguideways for anchoring one of said body members to the casing, andmeans operated by the relative downward movement of the upper bodymember to actuate the perforator tool.

' Signed at Whittier, California this 5th day of February 1923.

' ROLAND R. CRUM.

